
#include<stdio.h>
#include<math.h>
int main()
{
	int a, b, c;
	double s, area, perimeter;
	scanf_s("%d%d%d", &a,&b,&c);
	scanf_s("sides of the triangle:\n");
	if (a + b > c&&a + c > b&&b + c > a)
	{
		s = (a + b + c) / 2.0;
		perimeter = 2 * s;
		area = sqrt(s * (s - a) * (s - b) * (s - c));
		printf("area=%.2f;perimeter=%.2f\n",perimeter,area);
	}
	else
		printf("There sides do not correspond to a valid triangele\n");
	return 0;
}